Neither does anyone else, its one of those archaic units that changes slightly based on who is using it and hangs on in oil and gas industries, and also air conditioners and heaters.
It was defined as the amount of energy to raise one pound of water by one degree Fahrenheit at one atmosphere of pressure, but that amount of energy depends on the starting temperature of the water, and different things use different starting points, so it ranges from about 1054 to 1059 joules
Why would the amount of energy required to increase the temperature of a defined mass of water depend on the temperature? This goes against the idea of specific heat
(editing to add - I didn't realize that water's specific heat has a temperature dependence and changes around 5% over reasonable indoor temperatures
No, it doesn't go against the idea of specific heat. You may be thinking of ideal gases and even then specific heat may or may not be constant: https://en.wikipedia.org/wiki/Perfect_gas
The ideal gas model assumes point particles with no interparticle interactions, while all the interesting stuff with regards to all kinds of specific heat happens due to these things in... particular.
They're not saying the rate varies but the starting point. Going from 30C to 100C takes less energy than going from 20C to 100C even if specific heat remains physical. Both might get labeled a BTU.
They specifically said "one degree Fahrenheit", so the GP's question was "why does going from 30 F to 31 F take a different amount of energy than going from 20 F to 21 F?".
Traditionally it's not a "mass" of water, it's a pound (unqualified) of water.
There's an issue right there and one that cracks the door open to "how is pound of water created".
Leading into (depending on path to above) the issue of density of water, while famously and often described as incompressible, water reaches max density at 4 C, 3.99 degrees (Kelvin or Celsius) above water's triple point.
It is pretty simple and standardized. The spec sheet will list the cooling and heating output in kW, and then also the input in kW. The number they have displayed most prominently is the cooling output while the others will be in the specs.
'Go Wild' (John Ratey, Richard Manning) theorizes that the modern concept of bedrooms in which we segregate ourselves to sleep is a mismatch with our evolutionary established state. We would naturally lie in very close proximity of tribe and family for heat, contact and security. Sleeping and resting on one another out in the open. Perhaps pillows and blankets (esp weighted) serve as a proxy for this, not just temperature?
Well, this is probably a thing where humans are very diverse in their subjective experience.
I'd say this is definitely a noticeable thing with small children at family gatherings, birthday parties and the like. But I grew up in a household where both of my parents came from families where big family gatherings with even extended family was common, and I know not everyone has that kind of experience, so who knows how much of that is nature or nurture as well.
In my case however this has persisted well into adulthood: despite being a chronic insomniac who has a really hard time falling a sleep normally, at these types of social gatherings I often have to fight off falling asleep precisely because I feel comfortable and safe among friends and/or family (I wonder if that is in any way related to my ADHD).
Safety. If something creeps up hopefully one of you is partly awake to raise the alarm. I sometimes think cats are still like this, they seem to sleep very soundly around people but only snooze and are easily startled when isolated.
Is this a common thing? Sleeping without any sort of cover during the hot summer months (notably July and August) is the norm here (North Africa) and never heard of anyone who does it (AC or not).
Is this an American thing? Do people in warmer regions of the country (Texas, Florida, ...) also feel the same?
Speaking personally, I have the "must be covered" gene along with the "overheats easily at night" gene, so it's been a bit of a struggle hitting a balance. Right now a thin breathable quilt is the way to go, even in deep winter. Hard to explain really, but I feel anxious (and cold!) if my body is exposed, even if it's actually pretty hot in the room.
The best mitigation for this conflict seems to be those knitted blankets with the enormous holes. Terrible heat retention, and they're pretty heavy. That got the job done during a Texas summer on more than one occasion.
Here in India, when I was growing up it was normal to sleep without a cover in the summer (no ACs back then, only ceiling fans and perhaps an evaporation cooler in more luxurious circumstances). I remember when a friend and his cousin from Thailand was visiting and the power had just gone out. The temperature was in the early 40s (Celsius) but the Thai cousin who wanted to take a nap insisted on a thin cotton sheet as a cover. My friend and I were confused and kept telling him it's not a good idea but he couldn't fall asleep without it.
It is a thing and not only in U.S. I live in Greece and my girlfriend can’t sleep if she’s not covered by something even if it’s in the middle of August and it’s scorching Earth outside. She says she feels vulnerable without a cover. I on the other hand can’t sleep with a cover during summer.
As someone who lives in the Northeast US but travels to Florida somewhat regularly it amazes me how low people keep the AC. It’s common for people and places, or at least those I visit, to keep the AC lower than I keep my heat in the winter(18c). So sometimes I’m so cold I have to ask for additional blankets or bring a jacket to a place like a movie theater.
I'm born and raised in Sweden, now live in Spain, cannot fall asleep unless I have something covering me, but I can also not fall asleep while sweating... So in the hottest months (July and August), I tend to just use a bed sheet as the cover, does the trick.
Yes, it is totally a thing. We don't have a lot of hot nights in Denmark but when we do, we still sleep under a duvet, or maybe half under one and it is just as awful as it sounds.
Are you sure? That seems like the sort of thing people might just not do. It can't take that many brain cells for an uncomfrotably warm person to work out that more blankets make you more hotter -> less blankets makes you less hotter.
The article seems to provide very limited evidence that people sleep under blankets on hot nights and it sounds like a silly thing to do in the abstract. A lot of people would just remove the blanket when they get hot.
Sleeping with blankets is very comfortable. If the comfort outweighs the discomfort from being mildly hot, it makes sense. Personally I just run fans and/or AC such that I am still comfortable under my blanket, because the price I pay for electricity is worth far less to me than the comfort of sleeping with a blanket.
I consider the weighted blanket to be a very dangerous invention. Dangerous to my planning, that is. If I try take a quick 20 minute nap under it, I always sleep for 2 hours minimum. It's like an off switch for my brain.
Not just bedding but clothing was costly. High quality bedding (as well as clothing) still costs quite a bit of money especially once you take into account you need 2 sets for rotation. A proper quality set will run you $1000-2500 and there's luxury brands which will cost much more.
> "Nothing was saved except clothing and bedding. When Mrs. Wood saw that the house could not be saved, she put some sheets on the floor, threw all the clothes from bureau drawers and closets on the sheets, tied them up, and threw the out the window."
> "Well, wasn't that smart?" said Jessie. "That costs the most of anything, doesn't it, Aunt Jane? The family clothes and bedding?"
It is the only reason. I asked my wife one time why she sleeps under blankets when it's boiling hot (I do not); she said because there might be 'things in the night' so I asked if she thought these sheets will protect her; nope, but otherwise she doesn't sleep.
> "I barely know what a BTU is"
Neither does anyone else, its one of those archaic units that changes slightly based on who is using it and hangs on in oil and gas industries, and also air conditioners and heaters.
It was defined as the amount of energy to raise one pound of water by one degree Fahrenheit at one atmosphere of pressure, but that amount of energy depends on the starting temperature of the water, and different things use different starting points, so it ranges from about 1054 to 1059 joules
https://en.wikipedia.org/wiki/British_thermal_unit
Why would the amount of energy required to increase the temperature of a defined mass of water depend on the temperature? This goes against the idea of specific heat
(editing to add - I didn't realize that water's specific heat has a temperature dependence and changes around 5% over reasonable indoor temperatures
https://www.engineeringtoolbox.com/specific-heat-capacity-wa... )
No, it doesn't go against the idea of specific heat. You may be thinking of ideal gases and even then specific heat may or may not be constant: https://en.wikipedia.org/wiki/Perfect_gas
A specific heat is the amount of energy needed to raise a defined mass of a substance by a defined temperature.
What does that have to do with a perfect gas?
The ideal gas model assumes point particles with no interparticle interactions, while all the interesting stuff with regards to all kinds of specific heat happens due to these things in... particular.
Specific heat usually varies with the temperature itself.
They're not saying the rate varies but the starting point. Going from 30C to 100C takes less energy than going from 20C to 100C even if specific heat remains physical. Both might get labeled a BTU.
They specifically said "one degree Fahrenheit", so the GP's question was "why does going from 30 F to 31 F take a different amount of energy than going from 20 F to 21 F?".
Phase change?
Traditionally it's not a "mass" of water, it's a pound (unqualified) of water.
There's an issue right there and one that cracks the door open to "how is pound of water created".
Leading into (depending on path to above) the issue of density of water, while famously and often described as incompressible, water reaches max density at 4 C, 3.99 degrees (Kelvin or Celsius) above water's triple point.
I blessed to live in a country that uses kilowatts. That works wonderfully (and advertised as such) for AC units
Kilowatts as in power consumption or as in refrigeration or heating power? AC is somewhat not straightforward.
It is pretty simple and standardized. The spec sheet will list the cooling and heating output in kW, and then also the input in kW. The number they have displayed most prominently is the cooling output while the others will be in the specs.
'Go Wild' (John Ratey, Richard Manning) theorizes that the modern concept of bedrooms in which we segregate ourselves to sleep is a mismatch with our evolutionary established state. We would naturally lie in very close proximity of tribe and family for heat, contact and security. Sleeping and resting on one another out in the open. Perhaps pillows and blankets (esp weighted) serve as a proxy for this, not just temperature?
That would result in insanity for me. Is there any argument other than it seems like cave people must have?
Well, this is probably a thing where humans are very diverse in their subjective experience.
I'd say this is definitely a noticeable thing with small children at family gatherings, birthday parties and the like. But I grew up in a household where both of my parents came from families where big family gatherings with even extended family was common, and I know not everyone has that kind of experience, so who knows how much of that is nature or nurture as well.
In my case however this has persisted well into adulthood: despite being a chronic insomniac who has a really hard time falling a sleep normally, at these types of social gatherings I often have to fight off falling asleep precisely because I feel comfortable and safe among friends and/or family (I wonder if that is in any way related to my ADHD).
Safety. If something creeps up hopefully one of you is partly awake to raise the alarm. I sometimes think cats are still like this, they seem to sleep very soundly around people but only snooze and are easily startled when isolated.
Is this a common thing? Sleeping without any sort of cover during the hot summer months (notably July and August) is the norm here (North Africa) and never heard of anyone who does it (AC or not).
Is this an American thing? Do people in warmer regions of the country (Texas, Florida, ...) also feel the same?
Speaking personally, I have the "must be covered" gene along with the "overheats easily at night" gene, so it's been a bit of a struggle hitting a balance. Right now a thin breathable quilt is the way to go, even in deep winter. Hard to explain really, but I feel anxious (and cold!) if my body is exposed, even if it's actually pretty hot in the room.
The best mitigation for this conflict seems to be those knitted blankets with the enormous holes. Terrible heat retention, and they're pretty heavy. That got the job done during a Texas summer on more than one occasion.
Here in India, when I was growing up it was normal to sleep without a cover in the summer (no ACs back then, only ceiling fans and perhaps an evaporation cooler in more luxurious circumstances). I remember when a friend and his cousin from Thailand was visiting and the power had just gone out. The temperature was in the early 40s (Celsius) but the Thai cousin who wanted to take a nap insisted on a thin cotton sheet as a cover. My friend and I were confused and kept telling him it's not a good idea but he couldn't fall asleep without it.
It is a thing and not only in U.S. I live in Greece and my girlfriend can’t sleep if she’s not covered by something even if it’s in the middle of August and it’s scorching Earth outside. She says she feels vulnerable without a cover. I on the other hand can’t sleep with a cover during summer.
As someone who lives in the Northeast US but travels to Florida somewhat regularly it amazes me how low people keep the AC. It’s common for people and places, or at least those I visit, to keep the AC lower than I keep my heat in the winter(18c). So sometimes I’m so cold I have to ask for additional blankets or bring a jacket to a place like a movie theater.
Folks in the South don't consciously realize it, but they're setting the AC low to keep it running for its dehumidification.
These are the same folks who sweaters is its 80F outside. They can handle heat.
If ACs had the ability to run as dehumidifiers in convinced the temp would rise
I'm born and raised in Sweden, now live in Spain, cannot fall asleep unless I have something covering me, but I can also not fall asleep while sweating... So in the hottest months (July and August), I tend to just use a bed sheet as the cover, does the trick.
Yes, it is totally a thing. We don't have a lot of hot nights in Denmark but when we do, we still sleep under a duvet, or maybe half under one and it is just as awful as it sounds.
Are you sure? That seems like the sort of thing people might just not do. It can't take that many brain cells for an uncomfrotably warm person to work out that more blankets make you more hotter -> less blankets makes you less hotter.
The article seems to provide very limited evidence that people sleep under blankets on hot nights and it sounds like a silly thing to do in the abstract. A lot of people would just remove the blanket when they get hot.
Sleeping with blankets is very comfortable. If the comfort outweighs the discomfort from being mildly hot, it makes sense. Personally I just run fans and/or AC such that I am still comfortable under my blanket, because the price I pay for electricity is worth far less to me than the comfort of sleeping with a blanket.
No, I often sleep on top of my bed during the hot summer days. I also don't put myself under the blankets when I take a nap.
I don't know what TFA is talking about.
In France some people do and some people don't but it's definitely a thing
Recently discovered that "weighted blankets" are a thing.
https://en.wikipedia.org/wiki/Weighted_blanket
Weighted blankets are lovely if you have a neurodivergence that likes being enclosed (like me). But they are even more unbearable in hot weather
I consider the weighted blanket to be a very dangerous invention. Dangerous to my planning, that is. If I try take a quick 20 minute nap under it, I always sleep for 2 hours minimum. It's like an off switch for my brain.
Extremely comfy.
They didn't include a common reason for wanting at least a thin blanket on hot summer nights: it keeps the mosquitoes away!
I did not realize that things like sheets, blankets and pillows used to cost serious money.
Not just bedding but clothing was costly. High quality bedding (as well as clothing) still costs quite a bit of money especially once you take into account you need 2 sets for rotation. A proper quality set will run you $1000-2500 and there's luxury brands which will cost much more.
From the 1960 children's novel 'Mike's Mystery' from the Boxcar Children series by Gertrude Chandler Warner, at https://archive.org/details/mikesmystery00warn/page/28/mode/...
> "Nothing was saved except clothing and bedding. When Mrs. Wood saw that the house could not be saved, she put some sheets on the floor, threw all the clothes from bureau drawers and closets on the sheets, tied them up, and threw the out the window."
> "Well, wasn't that smart?" said Jessie. "That costs the most of anything, doesn't it, Aunt Jane? The family clothes and bedding?"
Clearly for better protection against monsters
It is the only reason. I asked my wife one time why she sleeps under blankets when it's boiling hot (I do not); she said because there might be 'things in the night' so I asked if she thought these sheets will protect her; nope, but otherwise she doesn't sleep.
Its so the monsters can't see you.